std::unordered_map<std::string, unsigned int> sent_messages_;
std::unordered_map<std::string, unsigned int> recv_messages_;
unsigned int collectives_count_ = 0;
std::unordered_map<std::string, unsigned int> sent_messages_;
std::unordered_map<std::string, unsigned int> recv_messages_;
unsigned int collectives_count_ = 0;